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Normalized glandular dose coefficients for digital breast tomosynthesis using detailed Chinese breast models

Nuclear Science and Techniques 2024年第5期35卷 42-59页

作者： Jia-Hao Wang rui Qiu An-Kang Hu Ye-Qi liu Zhen Wu Hui Zhang Jun-li li Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging Ministry of EducationTsinghua UniversityBeijing 100084China Joint Institute of Tsinghua University Nuctech Company Limited BeijingBeijing 100084China

The rise in breast cancer diagnoses among Chinese women has necessitated the use of X-ray breast screening,which carries a radiation *** study aimed to provide a dosimetry protocol for the Chinese female population to replace the traditional standard that utilizes simplified breast models,for the accurate estimation of the mean glandular dose of a patient undergoing digital breast tomosynthesis(DBT).The first set of detailed Chinese female breast models and representative breast parameters was *** backscatter radiation and computational efficiency,we improved the combination of these models and the Chinese reference adult female whole-body voxel *** acquisition for four commercial DBT systems that are widely employed in China was simulated using the Monte Carlo method to obtain the normalized glandular dose coefficients of DBT(D_(gN)^(DBT))and the glandular depth dose(D_(g)^(dep)(z))for different breast characteristics and X-ray *** calculated a series of D_(gN)^(DBT) values for breasts with different percentage mass glandularities(5%,25%,50%,75%,and 100%)and compressed breast thicknesses(2,3,4,5,6,and 7 cm)at various tube potentials(25,28,30,32,35,and 49 kV)and target/filter combinations(W/Rh,W/Al,Mo/Mo,Rh/Rh,and Rh/Ag).The parameter dependence of the breast characteristics and beam conditions on D_(gN)^(DBT) in detailed breast models was *** D_(gN)^(DBT) results were 14.6-51.0%lower than those of the traditional dosimetry standard in *** difference in D_(gN)^(DBT) was mainly due to a decrease in the depth of the main energy deposition area caused by the glandular distribution along the depth *** results obtained in this study may be used to improve breast dosimetry in China and provide more detailed information on risk assessment during DBT.

关键词： Digital breast tomosynthesis Normalized glandular dose coefficients Detailed breast model Monte Carlo simulation

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Technological advancement and industrialization path of Sinopec in carbon capture,utilization and storage,China

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Energy Geoscience 2024年第1期5卷 204-211页

作者： Yang li rui Wang Qingmin Zhao Zhaojie Xue China Petroleum&Chemical Corporation Beijing100728China Sinopec Exploration&Production Research Institute Beijing100083China

Carbon capture,utilization and storage(CCUS)technology is an important means to effectively reduce carbon emissions from fossil energy combustion and industrial *** the crisis of climate change,CCUS has attracted increasing attention in the *** technology as developed rapidly in China is technically feasible for large-scale application in various *** R&D and demonstration of CCUS in China Petroleum&Chemical Corporation(Sinopec)are summarized,including carbon capture,carbon transport,CO_(2)enhanced energy recovery(including oil,gas,and water,etc.),and comprehensive utilization of CO_(2).Based on the source-sink matching characteristics in China,two CCUS industrialization scenarios are proposed,namely,CO_(2)-EOR,CO_(2)-driven enhanced oil recovery using centralized carbon sinks in East China and CO_(2)-EWR,CO_(2)-driven enhanced water recovery(EWR)using centralized carbon sources from the coal chemical industry in West ***,a CCUS industrialization path from Sinopec's perspective is suggested,using CO_(2)-EOR as the major means and CO_(2)-EWR,CO_(2)-driven enhanced gas recovery(CO_(2)-EGR)and other utilization methods as important supplementary means.

关键词： Carbon capture Transport Enhanced energy recovery Comprehensive utilization Industrialization path

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Self-doping active sites in microbe-derived carbonaceous electrocatalysts for the oxygen reduction reaction performance

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Nano Research 2024年第8期17卷 6803-6819页

作者： Xiaofeng Xiao Xiaochun Tian Junpeng li Fan Yang rui Bai Feng Zhao Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

Microorganisms are rich in heteroatoms,which can be self-doped to form active sites during pyrolysis and loaded on microbederived carbonaceous *** recent years,microbe-derived carbonaceous materials,characterized with abundant selfdoping sites,have been continuously developed as cost-effective electrocatalysts for oxygen reduction reaction(ORR).To fully unlock the catalytic potential of microbe-derived carbonaceous materials,a comprehensive analysis of catalytic sites and mechanisms for ORR is *** paper provides a summary of the ORR catalytic performance of microbe-derived carbonaceous materials reported to date,with a specific focus on the self-doping sites introduced during their pyrolytic *** highlights the mono-or co-doping sites involving nonmetallic elements such as oxygen(O),nitrogen(N),phosphorus(P),and sulfur(S)atoms,as well as covers the doping of metallic iron(Fe)atoms with various coordination configurations in microbe-derived carbonaceous *** the impact of these self-doping sites on ORR catalytic performance can guide the design of doping sites in microbe-derived carbonaceous *** approach has the potential to maximize electrocatalytic activity of microbe-derived carbonaceous materials and contributes to the development of more efficient and cost-effective carbonaceous electrocatalysts.

关键词： electrocatalysis heteroatoms self-doped single atom catalyst microbe-derived carbonaceous material

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Numerical Analysis of Perforation during Hydraulic Fracture Initiation Based on Continuous-Discontinuous Element Method

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 2103-2129页

作者： rui Zhang lixiang Wang Jing li Chun Feng Yiming Zhang School of Civil and Transportation Engineering Hebei University of TechnologyTianjin300401China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing100190China School of Civil Engineering and Architecture Zhejiang Sci-Tech UniversityHangzhou310018China Jinyun Institute Zhejiang Sci-Tech UniversityLishui321400China

Perforation is a pivotal technique employed to establish main flow channels within the reservoir formation at the outset of hydraulic fracturing *** perforation designs is critical for augmenting the efficacy of hydraulic fracturing and boosting oil or gas *** this study,we employ a hybrid finite-discrete element method,known as the continuous–discontinuous element method(CDEM),to simulate the initiation of post-perforation hydraulic fractures and to derive enhanced design *** model incorporates the four most prevalent perforation geometries,as delineated in an engineering technical ***-world perforations deviate from the ideal cylindrical shape,exhibiting variable cross-sectional profiles that typically manifest as an initial constriction followed by an expansion,a feature consistent across all four perforation *** simulations take into account variations in perforation hole geometries,cross-sectional diameters,and perforation *** findings show that perforations generated by the 39g DP3 HMX perforating bullet yield the lowest breakdown pressure,which inversely correlates with increases in sectional diameter and perforation ***,this study reveals the relationship between breakdown pressure and fracture degree,providing valuable insights for engineers and designers to refine perforation strategies.

关键词： Hydraulic fracturing real perforation shape breakdown pressure perforation layout design CDEM

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Adaptive Dead-Time Modulation Scheme for Bidirectional LLC Resonant Converter in Energy Router

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1710-1721页

作者： Chenghao Sun Qiuye Sun rui Wang Yuyang li Dazhong Ma College of Information Science and Engineering Northeastern UniversityShenyang 110819China

Although the dead-time optimization design of resonant converters has been widely researched,classical design methods focus more on achieving zero-voltage switching(ZVS)*** body diode loss is always ignored,which results in low-efficiency of the converter,especially,in energy router(ER).To deal with this problem,this paper proposes an adaptive deadtime modulation scheme for bidirectional LLC resonant converters in ***,the power loss of the MOSFET is analyzed based on the ***,a novel dead-time optimization modulation principle is *** can eliminate the body diode loss of MOSFET compared with existing *** on the optimization modulation principle,this paper proposes an adaptive dead-time modulation *** this end,the converter adopting the scheme no longer needs to calculate dead-time,which simplifies the parameter design ***,this scheme enables dead-time to dynamically change with working conditions according to the dead-time optimization modulation *** these effects,the ZVS operation is achieved,and the body diode loss of MOSFET is also ***,a digital implementation method is designed to make the proposed modulation scheme have fast-transient ***,experimental results show that the proposed dead-time modulation scheme enables converters to achieve ZVS operation in all working conditions,and has higher efficiency than classical dead-time design methods.

关键词： Adaptive modulation bidirectional LLC body diode loss dead-time energy router ZVS

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Design and fabrication of Nd-Fe-B magnet with excellent thermal stability

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Journal of Rare Earths 2024年第5期42卷 980-986,I0006页

作者： rui Han Shengzhi Dong Dong li Dongmin Zhang Hongsheng Chen Jiyuan Xu George CHadjipanayis Zhuolin li Ying Zhang Wei li Division of Functional Materials Research Central Iron and Steel Research InstituteBeijing100081China Department of Physics and Astronomy Sharp Lab University of DelawareNewarkDE19716USA Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing100190China

A novel Nd-Fe-B type permanent magnet with excellent thermal stability was designed by Co replacing Fe in the main phase and the grain boundary *** remanence and coercivity temperature coefficient reach 0.058%/℃and 0.465%/℃in the te mperature range from 25 to 100℃,which are much lower than those of commercial Nd-Fe-B *** enhanced Curie temperature is obtained for the novel magnet due to the Co substitution,which significantly improves the operating *** microstructure result reveals that an amorphous phase exists in the intergranular grains which is probably responsible for the deterioration of intrinsic *** work can provide a reference for the design and optimization of components of sintered Nd-Fe-B magnets with excellent thermal stability.

关键词： Thermal stability Remanence temperature coefficient Operating temperature Atomic substitution Rare earths

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On the Performances of Estimating Stellar Atmospheric Parameters from CSST Broad-band Photometry

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Research in Astronomy and Astrophysics 2024年第4期24卷 161-173页

作者： rui-Feng Shi Yang Huang Xin-Yi li Hua-Wei Zhang School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China South-Western Institute for Astronomy Research Yunnan UniversityKunming 650500China CAS Key Lab of Optical Astronomy Key Laboratory of Space Astronomy and TechnologyNational Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China College of Physics and Electronic Engineering Qilu Normal UniversityJinan 250200China Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China

Deriving atmospheric parameters of a large sample of stars is of vital importance to understand the formation and evolution of the Milky *** surveys,especially those with near-ultraviolet filters,can offer accurate measurements of stellar parameters,with the precision comparable to that from low/medium resolution *** this study,we explore the capability of measuring stellar atmospheric parameters from Chinese Space Station Telescope(CSST)broad-band photometry(particularly in the near-ultraviolet bands),based on synthetic colors derived from model *** find that colors from the optical and near-ultraviolet filter systems adopted by CSST show significant sensitivities to the stellar atmospheric parameters,especially the *** to our mock data tests,the precision of the photometric metallicity is quite high,with typical values of0.17 and 0.20 dex for dwarf and giant stars,*** precision of the effective temperature estimated from broad-band colors are within 50 K.

关键词： methods:data analysis stars:abundances surveys

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Attention Markets of Blockchain-Based Decentralized Autonomous Organizations

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1370-1380页

作者： Juanjuan li rui Qin Sangtian Guan Wenwen Ding Fei lin Fei-Yue Wang State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China Faculty of Innovation Engineering Macao University of Science and TechnologyMacao 999078China State Key Laboratory for Management and Control of Complex Systems Chinese Academy of SciencesBeijing 100190 Faculty of Innovation Engineering Macao University of Science and TechnologyMacao 999078China IEEE

The attention is a scarce resource in decentralized autonomous organizations(DAOs),as their self-governance relies heavily on the attention-intensive decision-making process of“proposal and voting”.To prevent the negative effects of pro-posers’attention-capturing strategies that contribute to the“tragedy of the commons”and ensure an efficient distribution of attention among multiple proposals,it is necessary to establish a market-driven allocation scheme for DAOs’***,the Harberger tax-based attention markets are designed to facilitate its allocation via continuous and automated trading,where the individualized Harberger tax rate(HTR)determined by the pro-posers’reputation is ***,the Stackelberg game model is formulated in these markets,casting attention to owners in the role of leaders and other competitive proposers as *** equilibrium trading strategies are also discussed to unravel the intricate dynamics of attention ***,utilizing the single-round Stackelberg game as an illustrative example,the existence of Nash equilibrium trading strategies is ***,the impact of individualized HTR on trading strategies is investigated,and results suggest that it has a negative correlation with leaders’self-accessed prices and ownership duration,but its effect on their revenues varies under different *** study is expected to provide valuable insights into leveraging attention resources to improve DAOs’governance and decision-making process.

关键词： Attention decentralized autonomous organizations Harberger tax Stackelberg game.

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Surgical techniques to prevent delayed gastric emptying after pancreaticoduodenectomy

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 449-457页

作者： Peng Duan Lu Sun Kai Kou Xin-rui li Ping Zhang Department of Hepatobiliary and Pancreatic Surgery General Surgery Centerthe First Hospital of Jilin UniversityChangchun 130021China Department of Dental Implantology Hospital of StomatologyJilin UniversityChangchun 130021China

Background: Delayed gastric emptying(DGE) is one of the most common complications after pancreaticoduodenectomy(PD). DGE represents impaired gastric motility without significant mechanical obstruction and is associated with an increased length of hospital stay, increased healthcare costs, and a high readmission rate. We reviewed published studies on various technical modifications to reduce the incidence of DGE. Data sources: Studies were identified by searching Pub Med for relevant articles published up to December 2022. The following search terms were used: “pancreaticoduodenectomy”, “pancreaticojejunostomy”, “pancreaticogastrostomy”, “gastric emptying”, “gastroparesis” and “postoperative complications”. The search was limited to English publications. Additional articles were identified by a manual search of references from key articles. Results: In recent years, various surgical procedures and techniques have been explored to reduce the incidence of DGE. Pyloric resection, Billroth II reconstruction, Braun's enteroenterostomy, and antecolic reconstruction may be associated with a decreased incidence of DGE, but more high-powered studies are needed in the future. Neither laparoscopic nor robotic surgery has demonstrated superiority in preventing DGE, and the use of staplers is controversial regarding whether they can reduce the incidence of DGE. Conclusions: Despite many innovations in surgical techniques, there is no surgical procedure that is superior to others to reduce DGE. Further larger prospective randomized studies are needed.

关键词： Pancreaticoduodenectomy Delayed gastric emptying Postoperative complications Surgical techniques

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Effects of Acupotomy on Immobilization-Induced Gastrocnemius Contracture and Fibrosis in Rats via Wnt/β-Catenin Signaling

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Chinese Journal of Integrative Medicine 2024年第7期30卷 633-642页

作者： HU rui PAN Jun-kang li Jia-hui ZHANG Han li Shao-rong ZHANG Yi School of Acupuncture-Moxibustion and Tuina Beijing University of Chinese MedicineBeijing100029China Acupuncture Department Kunming Municipal Hospital of Traditional Chinese MedicineKunming650500China

Objective To determine whether acupotomy ameliorates immobilization-induced muscle contracture and fibrosis via Wnt/β-catenin signaling *** Thirty Wistar rats were randomly divided into 5 groups(n=6)by a random number table,including control,immobilization,passive stretching,acupotomy,and acupotomy 3 weeks(3-w)*** rat model of gastrocnemius contracture was established by immobilizing the right hind limb in plantar flexion for 4 *** in the passive stretching group received passive stretching at gastrocnemius,a daily series of 10 repetitions for 30 s each at 30-s intervals for 10 consecutive *** in the acupotomy and acupotomy 3-w groups received acupotomy once and combined with passive stretching at gastrocnemius a daily series of 10 repetitions for 30 s each at 30-s intervals for 10 consecutive ***,rats in the acupotomy 3-w group were allowed to walk freely for 3 weeks after 10-day *** treatment,range of motion(ROM),gait analysis[i.e.,paw area,stance/swing and maximum ratio of paw area to paw area duration(Max dA/dT)],gastrocnemius wet weight and the ratio of muscle wet weight to body weight(MWW/BW)were *** morphometric and muscle fiber cross-sectional area(CSA)were assessed by hematoxylin-eosin ***-related mRNA expressions(i.e.,Wnt 1,β-catenin,axin-2,α-smooth muscle actin,fibronectin,and types I and III collagen)were measured using real-time quantitative polymerase chain *** 1,β-catenin and fibronectin concentrations were measured by enzyme-linked immunosorbent *** I and III collagen in the perimysium and endomysium were analyzed using *** Compared with the control group,ROM,gait function,muscle weight,MWW/BW and CSA were significantly decreased in the immobilization group(all P<0.01),while protein levels of types I and III collagen,Wnt 1,β-catenin,fibronectin and mRNA levels of fibrosis-related genes were obviously increased(all P<0.01).Tr

关键词： acupotomy immobilization muscle contracture muscle fibrosis Wnt/β-catenin signaling

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